Which laws govern the rights and restrictions of federally subsidized tenants?

when a federally subsidised tenant has an issue, or has a request but is denied a satisfactory response or result that another tenant not subsidised enjoys because city law allows liberties the property management of the first tenant refuses to allow saying,"we do not have to follow city law/policy regarding rights because they receive federal money (making them exempt from city laws, rather federal laws) which laws spell out the rights of a federally subsidised tenant? This city's Rent arbitration and stabilisation board officially says that subsidised tenants are out of jurisdiction and they cannot help in any matter regarding.